Preheat oven to 425 degrees F. Line a muffin tin with paper liners.
In a large bowl, add wet ingredients. Whisk to combine.
Add dry ingredients to the bowl with the wet ingredients. Stir until just combined. Fold in the chocolate chips.
Fill the tins 3/4 full with batter. Nestle 3 mini marshmallows on top of each muffin and sprinkle the batter with 1 teaspoon of peppermint chips. Turn the oven temperature down to 350 degrees F. and place the muffins in the oven. Bake 18-20 minutes, or until a toothpick inserted in the center comes out with moist crumbs. Do not over bake.
Allow the muffins to cool in the tins for 5 minutes before transferring to a wire rack to cool completely. Serve warm or cool completely and store in an airtight container for up to 2 days.